Samantha Caine is a schoolteacher in small-town
Honesdale, Pennsylvania, living with her boyfriend Hal and her daughter Caitlin. Eight years earlier, she was found on a New Jersey beach, pregnant with Caitlin, and totally amnesiac. Having never remembered her real name, "Samantha" has hired several ineffective private investigators to discover her past, the latest being the down-on-his-luck Mitch Henessey. Over
Christmas, Samantha is involved in a car accident and suffers a mild concussion; upon recovering, she finds she possesses skills with a knife that she cannot explain. Shortly thereafter, their home is broken into by "One-Eyed Jack", a convict who escaped from jail after seeing Samantha's face on television. Samantha demonstrates her fighting prowess by killing Jack bare-handed. Fearing she poses a danger to Hal and Caitlin, she leaves with Mitch, who has found a suitcase belonging to her, to find answers. The suitcase contains a note directing them to Dr. Nathan Waldman. They arrange to meet at a train station, unaware that government agents are tapping his calls. En route, Samantha discovers the bottom of the suitcase contains a disassembled
sniper rifle which she can expertly reassemble, along with other weapons. When Samantha and Mitch go to meet Waldman at the station, they are attacked by a team of agents who shoot numerous bystanders, but they escape with Waldman's help. The doctor informs her that she is really an expert
CIA assassin, Charlene Elizabeth "Charly" Baltimore, who had disappeared eight years earlier. Unsure if they can trust Waldman, Samantha and Mitch leave him behind and seek another contact named on a note in the suitcase, Luke, believing he may be Charly's fiancé. Waldman catches up with them, trying to warn them that Luke is actually Charly's last target, "Daedalus." However, Luke kills Dr. Waldman before he can warn them. Samantha is then tortured with repeated near-drowning experiences for information. During this process, her real identity fully resurfaces and her memory returns. Samantha frees herself, kills Luke, and escapes with Mitch. She completes her physical transformation back to Charly, cutting her hair and dying it platinum blonde. Charly realizes that her "Samantha Caine" personality was a cover to get near Daedalus eight years earlier. A
psychological-operations specialist named Timothy, with whom Charly once had a romantic relationship, kidnaps Caitlin. Charly traces his call, in which he demands she trade herself for the girl. She soon finds them in
Niagara Falls. Charly and Mitch learn about Daedalus' involvement in "Project Honeymoon", which she disrupted on her mission, resulting in One-Eyed Jack's incarceration. The project was intended to be a
false flag chemical bomb detonation in Niagara Falls, planned by the
CIA pinned on
Islamic terrorists to secure more funding. The attack is being restaged by Timothy and a new group, led by CIA Director Leland Perkins. In Niagara Falls, he captures Mitch and Charly. She reveals that Timothy is Caitlin's biological father and implores him not to hurt their daughter. However, he is ultimately unmoved, locking Charly and Caitlin in a walk-in freezer to kill them. Charly and Caitlin break out by detonating barrels of kerosene and then freeing Mitch, who helps Charly attack the staging area. This forces Timothy to launch the attack early. Then, Caitlin locks herself in a cage on the truck that, unbeknownst to her, is carrying the bomb. Charly chases the truck, overpowers its driver, diverts it from a Christmas parade, and overturns it on the
Niagara Falls International Bridge leading to Canada. Charly frees Caitlin but they cannot get away from the bomb, which is about to explode, as Timothy and his agents attack them from a helicopter. Mitch suddenly arrives in a car, picking up Charly and Caitlin and entering Canada just before the bomb explodes. The blast kills Timothy and his forces and destroys the bridge. In an epilogue, Charly has returned to her assumed identity as Samantha Caine. Moving with Caitlin and Hal to a remote farmhouse, she declines an offer from the
POTUS to join the
State Department (possibly rejoining the CIA). Mitch enjoys the publicity attracted by his role in the crisis and is interviewed by
Larry King on television about Perkins, who was indicted for treason. ==Cast==